1. Field of the Invention
The present invention relates to a method of and apparatus for wrapping loadable objects in which a loadable object brought in as a mass is wrapped by spirally winding film around the object, both about a horizontal axis and about a vertical axis thereof.
2. Description of the Prior Art
Wrapping methods and apparatus of the type described above have been known in the art as shown and described in JP 59-46845 B and JP 8-508223 A.
JP 59-46845 B, referred to as the first prior art below, discloses an arrangement in which a loadable object is placed on a conveyor whose upper and lower surfaces move in an identical direction at an identical speed. A web made of stretchable material is wound around both the conveyor and the loadable object being carried by the conveyor. The loadable object is allowed to move beyond a downstream end of the conveyor to come off the conveyor where shrinkage of the web causes the loadable object alone to be wrapped thereby.
JP 8-508223 A, referred to as the second prior art below, describes in one of its intended forms of implementation an arrangement in which a web is wound around a loadable object, on a first table, about a horizontal axis and is thereby wrapped. The object so wrapped is then moved onto a second table, which is rotated about a vertical axis of the second table to further wrap a web around the object in a direction perpendicular to the direction in which the object is wrapped on the first table.
The second prior art also describes in another form of implementation contemplated, the use of a wrapping device that is revolvable about a vertical axis in an arrangement in which a loadable object is rotatable about a horizontal axis. Thus, a web may be wrapped around the loadable object about a vertical axis by revolving the wrapping device about the vertical axis, and about a horizontal axis by rotating the loadable object about the horizontal axis.
The capability by the first prior art of wrapping a web only about a horizontal axis is inconveniently unsuitable to wrap, and thereby to package, three-dimensional objects.
Also, while the second prior art permits a web to be wrapped around a loadable object about both horizontal and vertical axes thereof, if its one form of implementation is adopted in which the object is wrapped in dissimilar directions, it is required that the object be placed from the first to the second table, that a web roll be tilted 90 degrees while a web is being wrapped around the object, and moreover that the second table be rotated. Therefore, not only is a cumbersome double wrapping operation entailed, but also an apparatus for practicing this operation becomes inconveniently complex in terms of mechanisms.
In the other form of implementation of the second prior art, a technique that is capable of doubly wrapping web material around a loadable object resting at the same position, about both vertical and horizontal axes, a need to include two independent mechanisms for wrapping web material about the horizontal and vertical axes, respectively, makes equipment again inconveniently complex and large-scaled.
Further as described in the second prior art, the technique of wrapping film in the form of a continuous strip doubly around a loadable object about both axes is efficient to thoroughly cover an entire surface of the object therewith, but such wrappage is weak in strength and gives rise to a problem in that if the wrappage is hit by something sharp it may easily rupture to allow its contents to escape.
With the foregoing state of art taken into account, it is an object of the present invention to provide a method of wrapping a loadable object using a conventional wrapping machine for wrapping film around loadable objects about a horizontal axis, which method permits film to be easily wrapped around the loadable object both about its horizontal and about its vertical axes. An additional object of the present invention is a wrapping apparatus for use in carrying out the method.
Another object of the present invention is to provide a wrapping technique whereby a continuous strip of film, and a continuous string of film formed by compressing such a continuous strip of film, are both spirally wound around a loadable object about both a horizontal and a vertical axis thereof, which technique makes wrapping much less rupturable and prevents run-out of dust or refuse from the loadable object.
In order to achieve the objects mentioned above, the present invention provides in one method aspect thereof a method of wrapping a loadable object, which method comprises: revolving a film feeder about a horizontal axis along a circular path while advancing a loadable object through the circular path and along a path extending in a direction of the horizontal axis from a first side towards a second side to cause film from the film feeder to be wound spirally around the loadable object, thereby wrapping at least a portion or a major part of the loadable object; thereafter rotating the loadable object in a horizontal plane by an angle of 90 degrees; and advancing the loadable object along the horizontal path from the second side towards the first side while revolving the film feeder about the horizontal axis along the circular path to cause film from the film feeder to be again wound spirally around the loadable object, thereby completing wrapping the loadable object.
The present invention also provides a method of wrapping a loadable object, which method comprises: revolving a film feeder about a horizontal axis along a circular path while advancing a loadable object through the circular path and along a path extending in a direction of the horizontal axis from a first side towards a second side to cause film from the film feeder to be wound spirally around the loadable object, thereby wrapping at least a portion or a major part of the loadable object; thereafter rotating the loadable object in a vertical plane by a phase angle of 90 degrees; and advancing the loadable object along the horizontal path from the second side towards the first side while revolving the film feeder about the horizontal axis along the circular path to cause film from the film feeder to be wound spirally again around the loadable object, thereby completing wrapping of the loadable object.
The present invention also provides a method of wrapping a loadable object, which method comprises: providing a film feeder for supplying a plurality of films, at least one of which is a continuous strip of film and at least another of which is a continuous string of film formed by compressing such a continuous strip of film; and revolving the film feeder about a horizontal axis along a circular path while advancing a loadable object through the circular path and along a path extending in a direction of the horizontal axis to cause at least one continuous strip of film and at least one continuous string of film from the film feeder to be wound spirally around the loadable object, thereby wrapping the loadable object with such at least one continuous strip and at least one continuous string of film.
In a specific form of an embodiment of the present invention, the loadable object is placed on a sleeve pallet that is adapted to accept a fork of a forklift, and film from the feeder is wound around both the loadable object and the sleeve pallet.
According to one apparatus aspect for carrying out one method described above, the present invention provides an apparatus for wrapping a loadable object, which apparatus comprises: a film feeder adapted for revolving about a horizontal axis along a circular path; and a bi-directional conveyor adapted to carry and advance a loadable object through the circular path in a direction of the horizontal axis from a first side towards a second side and from the second side towards the first side, whereby the film feeder so revolving in conjunction with the loadable object so advanced by the conveyor from the first side towards the second side causes film from the film feeder to be wound spirally around the loadable object, thereby wrapping at least a portion or a major part of the loadable object. The apparatus further comprises: a carrier table juxtaposed with the conveyor at the second side for receiving the loadable object having a continuous strip of film wound around it, rotating the received loadable object in a horizontal plane by an angle of 90 degrees, and then returning the rotated loadable object onto the conveyor, whereby the film feeder revolving as aforesaid in conjunction with the loadable object from the carrier table advanced by the conveyor as aforesaid from the second side towards the first side causes film from the film feeder to be again wound spirally around the loadable object, thereby completing wrapping of the loadable object.
The present invention also provides an apparatus for wrapping a loadable object, which apparatus comprises: a film feeder adapted for revolving about a horizontal axis along a circular path; and a bi-directional conveyor adapted to carry and advance the loadable object through the circular path in a direction of the horizontal axis from a first side towards a second side and from the second side towards the first side, whereby the film feeder so revolving in conjunction with the loadable object so advanced by the conveyor from the first side towards the second side causes film from the film feeder to be wound spirally around the loadable object, thereby wrapping at least a portion or a major part of the loadable object. The apparatus further comprises a carrier table juxtaposed with the conveyor at the second side for receiving the loadable object having a continuous strip of film wound around it, rotating the received loadable object in a vertical plane by an angle of 90 degrees, and then returning the rotated loadable object onto the conveyor, whereby the film feeder revolving as aforesaid in conjunction with the loadable object from the carrier table advanced by the conveyor as aforesaid from the second side towards the first side causes film from the film feeder to be again wound spirally around the loadable object, thereby completing wrapping of the loadable object.
The present invention also provides an apparatus for wrapping a loadable object, which apparatus comprises: a film feeder adapted for revolving about a horizontal axis along a circular path; and a conveyor adapted to carry and advance the loadable object through the circular path in a direction of the horizontal axis, whereby the film feeder so revolving in conjunction with the loadable object so advanced by the conveyor causes film from the film feeder to be wound spirally around the loadable object, thereby wrapping the loadable object. The film feeder comprises a plurality of film feeders, at least one of which includes in a film feed outlet thereof a squeeze roller device for squeezing a continuous strip of film being fed out so as to narrow its width and thereby to provide a continuous string of film, whereby the loadable object is wound spirally and thereby wrapped with such continuous strip and continuous string of film.
The constructions mentioned above allow a loadable object to move forth and back through a conventional wrapping machine, and during such bi-directional movement of the loadable object, film is wound around the loadable object over its entire orthogonal six surfaces and doubly on both its upper and lower or front and back surfaces with strips of intersecting fim.
Also, forming film from a continuous strip into a continuous string in at least one film feeder allows a loadable object to be wound and thereby tightly wrapped with a wider form of film and a compressed form of film.
Further, using a sleeve pallet allows a fork of a forklift, in carrying a film wrapped loadable object together with the sleeve pallet, to be accepted by the sleeve pallet upon breaking the film.
In order to achieve the objects mentioned above, the present invention provides in another aspect thereof a method of wrapping a loadable object, which method comprises: supplying a film wrapping machine with a loadable object by extruding the loadable object from a loadable object feeder through a press nozzle into an area defined between a pair of guide plates within a circular path in the film wrapping machine; and revolving a film feeder about a horizontal axis along the circular path while advancing the supplied loadable object through the circular path and along a path extending in a direction of the horizontal axis to cause film from the film feeder to be spirally wound around the loadable object with a portion of the press nozzle and the guide plates inclusive.
The present invention also provides a method of wrapping a loadable object, which method comprises: revolving a film feeder about a horizontal axis along a circular path while advancing a loadable object through the circular path and along a path extending in a direction of the horizontal axis to cause film from the film feeder to be spirally wound around the loadable object about the horizontal axis; ceasing the film feeder from being revolved; and advancing the loadable object in a direction of a vertical axis while rotating the loadable object about the vertical axis to cause film to be wound spirally around the loadable object about the vertical axis. The film feeder comprises a plurality of film feeders positioned along the circular path, at least one of which is adapted to supply film in the form of a continuous strip, and at least another of which is adapted to form such a continuous strip of film into a continuous string of film and supply the latter, whereby the loadable object is wound and thereby wrapped with such at least one continuous strip and continuous string of film.
In another apparatus aspect for carrying out a method as described above, the present invention also provides an apparatus for wrapping a loadable object, which apparatus comprises: a film wrapping machine having an inlet for receiving a loadable object from a loadable object feeder, with the inlet having a press nozzle formed into a shape adapted to surround the loadable object from the loadable object feeder; a film feeder adapted for revolving about a horizontal axis along a circular path defined in the film wrapping machine; and a conveyor adapted to carry and advance the loadable object through the circular path in a direction of the horizontal axis, whereby the film feeder so revolving in conjunction with the loadable object so advanced by the conveyor causes film from the film feeder to be wound spirally around the loadable object, thereby wrapping the loadable object.
The present invention also provides an apparatus for wrapping a loadable object, which apparatus comprises: a film wrapping machine; a film feeder adapted for revolving about a horizontal axis along a circular path defined in the film wrapping machine; a conveyor adapted to carry and advance a loadable object from a loadable object feeder through the circular path in a direction of the horizontal axis from a first side to a second side, whereby the film feeder so revolving in conjunction with the loadable object so advanced by the conveyor from the first side towards the second side causes film from the film feeder to be wound spirally around the loadable object about the horizontal axis, whereon the film feeder ceases to be revolved; and a rotary table disposed adjacent to the second side for advancing the loadable object in a direction of a vertical axis while rotating the loadable object about the vertical axis to cause film to be wound spirally around the loadable object about the vertical axis. The film feeder comprises a plurality of film feeders, at least one of which is positioned for film to be paid out therefrom oriented parallel to the horizontal axis, and at least another of which is positioned for film to be paid out therefrom oriented parallel to the vertical axis.
According to a specific arrangement of the present invention, the film feeder includes: a film support shaft for carrying a roll of film; an inlet and an outlet roll adapted to be driven to guide and pay out film from the roll of film carried by the film support shaft; and a coupling mechanism interposed between the inlet and outlet rolls for establishing a relationship between these rolls such that the inlet roll rotates slower than the outlet roll rotates. The coupling mechanism is coupled to a shaft for the inlet roll and coupled via a centrifugal clutch to a shaft for the outlet roll.
According to another specific arrangement of the present invention, the above-mentioned rotary table has a conveyor mounted thereon and is adapted to move in a direction in which the conveyor conveys.
According to another specific arrangement of the present invention, the wrapping machine is movable towards and away from the loadable object feeder.
In the construction described above, while a loadable object is advancing horizontally, revolving the film feeders causes film paid out from one film feeder, so oriented that film is paid out parallel to the horizontal axis, to be wound in the form of a continuous strip spirally around the loadable object with a portion of the press nozzle and the guide plates inclusive, and causes film paid out from another film feeder, so oriented that film is paid out parallel to the vertical axis, to be wound in the form of a continuous string spirally around the loadable object with a portion of the press nozzle and the guide plates inclusive.
Also, in a state in which a film feeder ceases to revolve, if a loadable object on the rotary table is lifted and rotated about a vertical axis, a resultant change in the axis about which film is wound around the loadable object relative to vertical causes film paid out from that film feeder, which is so oriented that film is paid out parallel to the horizontal axis, to be wound in the form of a continuous string spirally around the loadable object, and causes film paid out from that film feeder, which is so oriented that film is paid out parallel to the vertical axis, to be wound in the form of a continuous strip spirally around the loadable object.
Consequently, moving the loadable object horizontally causes film to be wound spirally around the loadable object about the horizontal axis, and lifting and rotating the rotary table causes film to be wound spirally around the loadable object about the vertical axis.
Also, in each film feeder, if a rate of paying out film is low, slow rotation of the outlet roll leaves the centrifugal clutch deactuated and thus leaves both rolls rotating at a same peripheral speed. A rise in the rate of paying out film actuates the centrifugal clutch to couple the outlet roll and the coupling mechanism on the latter""s side via the centrifugal clutch. This causes the inlet roll to rotate slower than the outlet roll, and a difference in peripheral speed between the two rolls causes film to elongate or stretch where it is running between the rolls.
Also, the conveyor on the rotary table is made movable towards an arriving loadable object. Thus, by moving the conveyor to an upstream side of its direction of conveyance, placement of the loadable object onto the rotary table is facilitated.
Further, guiding through a press nozzle a loadable object supplied from a loadable object feeder into the wrapping machine prevents the loadable object from falling. Further, moving the wrapping machine away from the loadable object feeder creates a space therebetween where maintenance operations can readily be conducted. This also facilitates cleaning an environment of the wrapping machine.